// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/rand_util.h"

#include <nacl/nacl_random.h>
#include <stddef.h>
#include <stdint.h>

#include "base/logging.h"

namespace {

void GetRandomBytes(void* output, size_t num_bytes)
{
    char* output_ptr = static_cast<char*>(output);
    while (num_bytes > 0) {
        size_t nread;
        const int error = nacl_secure_random(output_ptr, num_bytes, &nread);
        CHECK_EQ(error, 0);
        CHECK_LE(nread, num_bytes);
        output_ptr += nread;
        num_bytes -= nread;
    }
}

} // namespace

namespace base {

// NOTE: This function must be cryptographically secure. http://crbug.com/140076
uint64_t RandUint64()
{
    uint64_t result;
    GetRandomBytes(&result, sizeof(result));
    return result;
}

void RandBytes(void* output, size_t output_length)
{
    GetRandomBytes(output, output_length);
}

} // namespace base
